You spend a billion dollars on airline security, and then the terrorists just go and beat it by stitching a bomb in their side pocket – at least according to one blogger, who has filmed himself defeating the hated "nude" body scanners at two American airports.

Well, kind of. What engineer Jon Corbett has certainly done is tapped into a wellstream of anger at the invasive nature of modern airport security, as laid down by the Transportation Security Administration, whose scans and patdowns come at some cost to passenger dignity. Health concerns over the back-scatter x-ray technology used in roughly half the scanners (as opposed to millimetre-wave machines) have also led the EU to put a moratorium on implementation in Europe, although most studies have dismissed any risk.

On his blog, TSA Out of Our Pants, Corbett enterprisingly demonstrates how he passed through scanners unchallenged at airports in Fort Lauderdale and Cleveland because, he claims, the dark shadow the object throws up on a scan is identical to the background.

What do the experts say? Yes and no. The only place such scanners are in use this side of the Atlantic is Manchester airport, where any passenger who alarms the metal detector is put through the body scanner. The airport says it is quicker and cheaper than the alternative of frisking. Of Corbett's experiment, spokesman Russell Craig said: "He's taken a small metal tin through. And the guards are looking for a threat object. That's not one. It's not a valid test. To say this shows it undermines airport security technology is totally wrong."

Aviation security expert Philip Baum, of Green Light, says: "Pretty much every system, you can fool." He says that scanners use avatars – not the kind of images Corbett has put up on his blog – so talk of "nude" scanners is unnecessarily sensational. But he has some sympathy with the idea that scanners are a colossal waste of money.

"Using advanced imaging technology has its benefit," he says, "providing you know what you're looking for. You need 67 machines to do the job of 20 metal detectors. So it's certainly not cost-effective – and it's questionable if it's effective in any case. You can't pick up internal carry – which is what drug smugglers do every day. And there is no technology currently screening people for explosives."

But he warns that traditional archway metal detectors have very little benefit apart from the deterrent effect.

Instead, he proposes a focused search – profiling passengers. Globally, airlines are keen to speed up and streamline security, a massively expensive, time-consuming and unpopular hassle. Currently under consideration by the international body Iata is the "checkpoint of the future" programme, which would divide travellers into known, trusted and others – giving some more likelihood of the unpleasantly intimate experiences readers of Corbett's blog recount in the comments. But only at the cost of providing ever more information – another civil liberties concern.

And, Baum says, even the trusted traveller can turn – if threatened or drugged. For airline passengers, especially perhaps the mildly more irradiated American ones, the days of having a security regime that, as Corbett puts it, "molests our families" are a long way from over.